Clean air insulated electrical equipment leakage simulation device and detection method

Abstract

A clean air insulated electrical equipment leakage simulation device and detection method are provided. One end of a GIL busbar is connected to a clean air charging device and a tracer gas charging device via an air charging pipeline and a three-way valve. A simulated leakage point is set on the GIL busbar, and a digital pressure gauge is provided on the air charging pipeline. Clean air is charged into the vacuum GIL busbar. When the digital pressure indication value reaches the rated pressure of the GIL busbar, the clean air charging is stopped. Tracer gas is charged into the GIL busbar filled with clean air. When the digital pressure indication value reaches the tracer gas partial pressure, the tracer gas charging is stopped. The simulated leakage point is connected to a leakage simulation gas circuit to simulate leakage. The time when different concentrations of tracer gas are detected at each simulated leakage point is recorded. The numerical relationship between the concentration of the tracer gas and the diffusion speed and direction in the GIL busbar is fitted. The present invention realizes leakage point detection of clean air insulated electrical equipment and provides data reference for subsequent on-site addition of tracer gas leak detection.

Description

Technical Field

[0001] The invention belongs to the technical field of insulating gas electrical equipment, and relates to a leakage simulation device and a detection method for clean air insulating electrical equipment. Background Art

[0002] In electrical equipment, most equipment insulation uses gas as the insulating medium. As the country proposes green energy, the insulating medium of electrical equipment has been replaced by other environmentally friendly gases instead of SF6 gas. The alternative gases that can now be used for electrical insulation are SF6 / N2 mixed gas and C4F7N / CO2 mixed gas. Although these mixed gases reduce the use of SF6 gas, they still use greenhouse gases.

[0003] In the existing technology, vacuum interrupter technology uses clean air as the insulating medium for environmentally friendly GIS combination electrical appliances. The entire electrical equipment does not use SF6 gas at all, fundamentally reducing the use of greenhouse gases. Clean air as an insulating medium in electrical equipment requires that the gas pressure (density) must meet the rated pressure requirements (the rated pressure of SF6 circuit breakers is 0.58MPa, and the minimum locking pressure is 0.52MPa). If a leak is detected in the equipment, causing the pressure in the gas chamber to be too low, it will affect the insulation of the equipment. The gas pressure can be detected in real time using a density meter with a digital remote control. However, the leak point of the equipment cannot be determined. If the leak point cannot be found, the gas leakage problem cannot be solved, and the operation and maintenance personnel need to replenish the gas from time to time. If the leakage is too large, the gas replenishment will be frequent.

[0004] Prior Art 1 (CN107430044B) proposes a system and method for testing for gas leaks through a gas flow component, using different tracer and carrier gases. Carrier gas is circulated through the outlet region of the gas flow component to purge the tracer gas from the outlet region. Spectral emissions from the carrier gas are monitored, indicating the amount of tracer gas purged. A test flow of tracer gas is introduced into the inlet region of the gas flow component, and the inlet pressure is increased in successive pressure increments. The presence of a gas leak is determined when a step change in the intensity of the monitored spectral emissions is detected following one of the pressure increments in the inlet pressure. Summary of the Invention

[0005] To address the deficiencies in the prior art, the present invention provides a clean air insulated electrical equipment leakage simulation device and detection method. This device solves the problem of leak point detection in clean air insulated electrical equipment. Tracer gas is added to the clean air, and the leak point is determined by detecting the tracer gas, completing equipment leak repair. The device can also evaluate the diffusion rate of tracer gas of different concentrations throughout the container, providing data reference for subsequent on-site tracer gas leak detection.

[0006] The present invention adopts the following technical solutions.

[0007] A clean air insulated electrical equipment leakage simulation device comprises a GIL busbar, one end of the GIL busbar is connected to an inflation pipeline via an inflation interface, and one end of the inflation pipeline is connected to a clean air inflation device and a tracer gas inflation device.

[0008] A digital pressure gauge is installed on the inflation pipeline; multiple simulated leakage points are set on the GIL busbar, and each simulated leakage point is connected to a leakage simulation gas circuit;

[0009] When charging the tracer gas into the GIL busbar filled with clean air, use a digital pressure gauge to read the tracer gas partial pressure and control the charging amount of the tracer gas to obtain different tracer gas partial pressures;

[0010] Under different tracer gas partial pressures, leakage simulation is performed on the leakage simulation gas circuit at each simulated leakage point, and the time when the tracer gas is detected at the simulated leakage point is obtained.

[0011] The other end of the inflation pipeline is connected to the common port of the three-way valve. The first port of the three-way valve is connected to the first pressure-stabilizing valve, the first stop valve and the clean air inflation device in sequence through the clean air output gas path; the second port of the three-way valve is connected to the second pressure-stabilizing valve, the second stop valve and the tracer gas inflation device in sequence through the tracer gas output gas path.

[0012] The first stop valve controls the on / off of the clean air output gas path, and the first pressure-stabilizing valve stabilizes the output air flow pressure of the clean air output gas path;

[0013] The second stop valve controls the on-off of the tracer gas output gas path, and the second pressure-stabilizing valve stabilizes the output gas flow pressure of the tracer gas output gas path.

[0014] The simulated leakage points are set at the front, middle, rear, top and bottom of the GIL busbar.

[0015] The leakage simulation gas circuit includes: a third stop valve, a third pressure-stabilizing valve, a micro-mass flow controller, and a gas pipeline; the third stop valve, the third pressure-stabilizing valve, and the micro-mass flow controller are connected through a pipeline.

[0016] The simulated leakage point is connected to one end of the third stop valve, the other end of the third stop valve is connected to one end of the third pressure stabilizing valve, and the other end of the third pressure stabilizing valve is connected to the air inlet of the micro mass flow controller.

[0017] At each simulated leakage point, the leakage rate simulated by the micro mass flow controller was 0.2 ml / min.

[0018] A measuring port is arranged at the gas outlet of the trace mass flow controller, and a tracer gas leak detector is arranged at the measuring port.

[0019] Clean air insulated electrical equipment leakage detection method, including:

[0020] Step 1, vacuum the GIL busbar;

[0021] Step 2: After filling the vacuum GIL busbar with clean air, the value indicated by the digital pressure gauge is used as the total pressure of the mixed gas;

[0022] Step 3: When charging the GIL busbar filled with clean air with tracer gas, the amount of tracer gas charged is controlled using the indication of the digital pressure gauge to obtain a plurality of gradually increasing tracer gas partial pressures, and a plurality of tracer gas partial pressure changes are obtained by calculation;

[0023] The concentration of the tracer gas in the mixed gas is calculated based on the ratio of the change in the tracer gas partial pressure to the total pressure of the mixed gas on the GIL busbar. The concentration of the tracer gas is controlled within the preset concentration range.

[0024] Step 4: Under different tracer gas partial pressures, the leakage rate at each simulated leakage point is controlled to be 0.2 ml / min, and each simulated leakage point is continuously detected, and the time when the tracer gas is detected at each simulated leakage point is recorded;

[0025] Step 5: Based on the test results at different tracer gas partial pressures, determine the relationship between the tracer gas concentration and the diffusion speed and direction of the tracer gas in the GIL busbar, which serves as the data basis for leakage detection of clean air insulated electrical equipment.

[0026] In step 2, the clean air charging device is turned on, and the three-way valve is rotated to the internal conduction state between the common port and the first port, and clean air is charged into the GIL busbar;

[0027] The rated pressure of the GIL busbar is set according to the manufacturer's requirements;

[0028] After stopping the charging of clean air, turn the three-way valve to the closed state and let it stand;

[0029] The rated pressure of the GIL busbar is taken as the total pressure of the mixed gas.

[0030] In step 3, the tracer gas charging device is turned on, and the three-way valve is rotated to the internal conduction state of the common port and the second port, and the tracer gas is charged into the GIL busbar filled with clean air; after stopping the tracer gas charging, the three-way valve is rotated to the closed state;

[0031] Among them, the indication of the digital pressure gauge is the partial pressure of the tracer gas.

[0032] The preset concentration range of the tracer gas is 0.1% to 0.2%.

[0033] In step 4, each simulated leakage point is continuously detected using a tracer gas leak detector, the time when the tracer gas is detected at each simulated leakage point is recorded, and the change in the tracer gas concentration is detected at the same time.

[0034] The beneficial effect of the present invention is that, compared with the prior art, the timely discovery and determination of the location of leakage points in electrical equipment using clean air as the insulating medium is of great significance to maintaining the pressure of the electrical equipment. Leaks can be discovered and repaired in a timely manner, the frequency of air replenishment can be reduced as much as possible, and the degradation of the insulation performance of the electrical equipment can be avoided to a certain extent.

[0035] It can evaluate the concentration or partial pressure ratio of tracer gas added to clean air to complete the detection of leak points. It can also evaluate the diffusion speed of tracer gas in different proportions in the entire container, providing data reference for subsequent on-site addition of tracer gas leak detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a structural schematic diagram of the clean air insulated electrical equipment leakage simulation device proposed by the present invention;

[0037] Figure 1 The reference numerals in the figures are described as follows:

[0038] 1-GIL busbar, 2-charging line, 3-digital pressure gauge, 4-leak point, 5-third stop valve, 6-third pressure-stabilizing valve, 7-micro mass flow controller, 8-measuring port, 9-charging interface, 10-clean air output path, 11-tracer gas output path, 12-first pressure-stabilizing valve, 13-first stop valve, 14-second pressure-stabilizing valve, 15-second stop valve, 16-tracer gas charging equipment, 17-clean air charging equipment; V1-three-way valve, com-common port of the three-way valve, A-first port of the three-way valve, B-second port of the three-way valve. DETAILED DESCRIPTION

[0039] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. The embodiments described in this application are only part of the embodiments of the present invention, not all of them. Based on the spirit of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0040] The clean air insulated electrical equipment leakage simulation device proposed by the present invention is as follows: Figure 1 As shown, it is connected to the GIL busbar 1, one end of the GIL busbar is connected to the clean air charging device 17 and the tracer gas charging device 16 through the charging pipeline 2, and multiple simulated leakage points 4 are set on the GIL busbar.

[0041] It is worth noting that one end of the GIL busbar is connected to a clean air charging device or a clean air source through an inflation pipeline, and at the same time, one end of the GIL busbar is connected to a tracer gas charging device or a tracer gas source through an inflation pipeline.

[0042] The clean air source includes a clean air tank, and the tracer gas source includes a tracer gas cylinder.

[0043] In a non-limiting preferred embodiment, the simulated leakage points proposed by the present invention are set at the front, middle, rear, top and bottom of the GIL busbar to achieve the diffusion of the tracer gas in all directions within the GIL busbar, such as Figure 1 As shown, points A, B, C and D are all set as simulated leakage points.

[0044] The leakage simulation gas circuit includes: a third stop valve, a third pressure-stabilizing valve, a trace mass flow controller, and a gas pipeline; the third stop valve, the third pressure-stabilizing valve and the trace mass flow controller are connected through a body pipeline.

[0045] At the simulated leakage point, a third stop valve 5, a third pressure-stabilizing valve 6, a trace mass flow controller 7 and a measuring port 8 are connected in series in sequence according to the gas flow direction.

[0046] Specifically, each simulated leak point is connected to one end of a third shutoff valve, the other end of which is connected to one end of a third pressure-stabilizing valve, and the other end of which is connected to the inlet of a micro-mass flow controller. A measurement port is provided at the outlet of the micro-mass flow controller. A tracer gas leak detector is placed at the measurement port.

[0047] Furthermore, a digital pressure gauge 3 is provided on the gas charging pipeline 2. The digital pressure gauge 3 is a high-precision digital pressure gauge that displays the total pressure of the mixed gas, the clean air partial pressure, and the tracer gas partial pressure in the GIL busbar.

[0048] Furthermore, one end of the inflation pipeline 2 is connected to the GIL busbar 1 through the inflation interface 9, and the other end of the inflation pipeline 2 is connected to the common port com of the three-way valve V1; the first port A of the three-way valve V1 is connected to the first pressure-stabilizing valve 12, the first stop valve 13 and the clean air inflation device 17 in sequence through the clean air output gas path 10; the second port B of the three-way valve V1 is connected to the second pressure-stabilizing valve 14, the second stop valve 15 and the tracer gas inflation device 16 in sequence through the tracer gas output gas path 11.

[0049] The first stop valve 13 is close to the gas outlet of the clean air charging device 17 , and the second stop valve 15 is close to the gas outlet of the tracer gas charging device 16 .

[0050] Specifically, clean air and tracer gas are generally stored in gas tanks or gas cylinders. The output airflow pressure will become smaller and smaller, resulting in unstable airflow. However, the GIL busbar gas distribution and inflation requires a stable flow rate. Therefore, a shut-off valve and a pressure-stabilizing valve are respectively provided on the output gas lines of clean air and tracer gas. The shut-off valve controls the on-off of the gas, and the pressure-stabilizing valve stabilizes the output airflow.

[0051] The first stop valve controls the on-off of the clean air output gas path, and the first pressure-stabilizing valve stabilizes the output airflow pressure of the clean air output gas path; the second stop valve controls the on-off of the tracer gas output gas path, and the second pressure-stabilizing valve stabilizes the output airflow pressure of the tracer gas output gas path.

[0052] Another aspect of the present invention provides a method for detecting leakage of clean air insulated electrical equipment, comprising:

[0053] Step 1: vacuum the GIL busbar and check whether the vacuum is qualified;

[0054] Step 2: After filling the vacuum GIL busbar with clean air, the value indicated by the digital pressure gauge is used as the total pressure of the mixed gas;

[0055] Preferably, in step 2, the clean air charging device is turned on, the three-way valve is rotated to the internal conduction state between the common port and the first port, and clean air is charged into the GIL busbar; the rated pressure of the GIL busbar is set according to the manufacturer's requirements; after stopping the charging of clean air, the three-way valve is rotated to the closed state and left to stand.

[0056] Since the concentration of the tracer gas is very small, the rated pressure of the GIL busbar is used as the total pressure of the mixed gas.

[0057] Step 3: When charging the GIL busbar filled with clean air with tracer gas, the amount of tracer gas charged is controlled using the indication of the digital pressure gauge to obtain a plurality of gradually increasing tracer gas partial pressures, and a plurality of tracer gas partial pressure changes are obtained by calculation;

[0058] The concentration of the tracer gas in the mixed gas is calculated based on the ratio of the change in the tracer gas partial pressure to the total pressure of the GIL bus mixed gas, and the concentration of the tracer gas is controlled within a preset concentration range.

[0059] As the tracer gas is charged, the tracer gas partial pressure gradually increases. Therefore, when the tracer gas is charged into the GIL busbar filled with clean air, the value indicated by the digital pressure gauge is used to control the charging amount of the tracer gas to obtain gradually increasing tracer gas partial pressures P1 and P2. Among them, P2 is greater than P1, and the difference between P1 and P2 is used as the change in tracer gas partial pressure.

[0060] In step 3, the tracer gas charging device is turned on, and the three-way valve is rotated to the internal conduction state of the common port and the second port, and the tracer gas is charged into the GIL busbar filled with clean air; after stopping the tracer gas charging, the three-way valve is rotated to the closed state;

[0061] Among them, the indication of the digital pressure gauge is the partial pressure of the tracer gas.

[0062] The preset concentration range of the tracer gas is 0.1% to 0.2%.

[0063] Step 4: Under different tracer gas partial pressures, control the leakage rate at each simulated leakage point to be 0.2 ml / min, continuously detect each simulated leakage point, and record the time when the tracer gas is detected at each simulated leakage point.

[0064] In step 4, each simulated leakage point is continuously detected using a tracer gas leak detector, the time when the tracer gas is detected at each simulated leakage point is recorded, and the change in the tracer gas concentration is detected at the same time.

[0065] Step 5: Based on the test results at different tracer gas partial pressures, determine the relationship between the tracer gas concentration and the diffusion speed and direction of the tracer gas in the GIL busbar, which serves as the data basis for leakage detection of clean air insulated electrical equipment.

[0066] The diffusion speed and direction of the tracer gas in the GIL busbar are related to the time when the tracer gas is detected at each simulated leakage point. By measuring or calculating the gas diffusion distance from the GIL busbar inflation inlet to each simulated leakage point, the relationship between the tracer gas concentration and the diffusion speed and direction of the tracer gas in the GIL busbar is obtained, which serves as the data basis for leakage detection of clean air insulated electrical equipment.

[0067] In a non-limiting preferred embodiment, the GIL busbar is vacuumed. After the vacuum is qualified, the clean air charging device, the first shut-off valve, and the first pressure-stabilizing valve are opened in sequence. When the common port com of the three-way valve V1 and the first port A are internally connected, clean air is input into the GIL busbar. When the digital pressure gauge shows the rated pressure of 580 kPa, the clean air charging is stopped and the three-way valve V1 is rotated to the closed state. After standing for 1 hour, the common port com and the second port B of the three-way valve V1 are internally connected. The tracer gas charging device, the second shut-off valve, and the second pressure-stabilizing valve are opened in sequence, and tracer gas is input into the GIL busbar.

[0068] In a non-limiting preferred embodiment, the volume proportion (i.e., concentration) of the tracer gas in the GIL busbar is 0.1% to 0.2%, and the rated pressure of the GIL busbar is 580 kPa. Since the volume proportion of the tracer gas is very small, 580 kPa can be regarded as the total pressure of the mixed gas, and the partial pressure range of the tracer gas is 0.58 to 1.16 kPa.

[0069] Within the tracer gas partial pressure range, tracer gas is introduced into the GIL busbar. Assuming the gas pressure rises by 0.68 kPa, the volume fraction (i.e., concentration) of the tracer gas in the mixed gas is calculated as: ρ = 100% × tracer gas partial pressure / GIL busbar total pressure = 100% * 0.68 / 580.68 = 0.117%. Tracer gas charging is stopped, and three-way valve V1 is closed. After the GIL busbar is fully charged, the micro-mass flow controller 7 at each simulated leak point simulates a leak rate of 0.2 ml / min. A tracer gas leak detector is connected to measurement port 8 and continuously monitors the four simulated leak points, recording the time at which tracer gas is detected at each simulated leak point.

[0070] In a non-limiting preferred embodiment, the concentration of the tracer gas is increased to raise the preset partial pressure of the tracer gas, and then the time when the tracer gas is detected at different leakage points is recorded respectively. For example, if tracer gas continues to be input into the GIL busbar, after the gas pressure increases by 0.78 kPa, the volume proportion of the tracer gas in the mixed gas is 0.78 / 580.78×100%=0.134%; after the gas pressure increases by 0.84 kPa, the volume proportion of the tracer gas in the mixed gas is 0.84 / 580.84×100%=0.145%; after the gas pressure increases by 0.95 kPa, the volume proportion of the tracer gas in the mixed gas is 0.97 / 580.97×100%=0.167%; after the gas pressure increases by 1 kPa, the volume proportion of the tracer gas in the mixed gas is 1 / 581×100%=0.172%; and after the gas pressure increases by 1.21 kPa, the volume proportion of the tracer gas in the mixed gas is 1.21 / 581.21×100%=0.2082%. The time when tracer gas is detected at different leak points is then recorded.

[0071] Based on the data, a timeline of different partial pressures of tracer gas and the detection of tracer gas at different leak points is drawn to provide guidance and suggestions for subsequent on-site addition of tracer gas.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the claims of the present invention.

Claims

1. A clean air insulated electrical equipment leakage simulation device, comprising a GIL busbar, one end of the GIL busbar being connected to an inflation pipeline via an inflation interface, one end of the inflation pipeline being connected to a clean air inflation device and a tracer gas inflation device, characterized in that: A digital pressure gauge is installed on the inflation pipeline; multiple simulated leakage points are set on the GIL busbar, and each simulated leakage point is connected to a leakage simulation gas circuit; When charging the tracer gas into the GIL busbar filled with clean air, use a digital pressure gauge to read the tracer gas partial pressure and control the charging amount of the tracer gas to obtain different tracer gas partial pressures; Under different tracer gas partial pressures, leakage simulation is performed on the leakage simulation gas circuit at each simulated leakage point, and the time when the tracer gas is detected at the simulated leakage point is obtained.

2. The clean air insulated electrical equipment leakage simulation device according to claim 1, characterized in that: The other end of the inflation pipeline is connected to the common port of the three-way valve. The first port of the three-way valve is connected to the first pressure-stabilizing valve, the first stop valve and the clean air inflation device in sequence through the clean air output gas path; the second port of the three-way valve is connected to the second pressure-stabilizing valve, the second stop valve and the tracer gas inflation device in sequence through the tracer gas output gas path.

3. The clean air insulated electrical equipment leakage simulation device according to claim 1, characterized in that: The first stop valve controls the on / off of the clean air output gas path, and the first pressure-stabilizing valve stabilizes the output air flow pressure of the clean air output gas path; The second stop valve controls the on-off of the tracer gas output gas path, and the second pressure-stabilizing valve stabilizes the output gas flow pressure of the tracer gas output gas path.

4. The clean air insulated electrical equipment leakage simulation device according to claim 1, characterized in that: The simulated leakage points are set at the front, middle, rear, top and bottom of the GIL busbar.

5. The clean air insulated electrical equipment leakage simulation device according to claim 1, characterized in that: The leakage simulation gas circuit includes: a third stop valve, a third pressure-stabilizing valve, a micro-mass flow controller, and a gas pipeline; the third stop valve, the third pressure-stabilizing valve, and the micro-mass flow controller are connected through a pipeline.

6. The clean air insulated electrical equipment leakage simulation device according to claim 5, characterized in that: The simulated leakage point is connected to one end of the third stop valve, the other end of the third stop valve is connected to one end of the third pressure stabilizing valve, and the other end of the third pressure stabilizing valve is connected to the air inlet of the micro mass flow controller.

7. The clean air insulated electrical equipment leakage simulation device according to claim 5, characterized in that: At each simulated leakage point, the leakage rate simulated by the micro mass flow controller was 0.2 ml / min.

8. The clean air insulated electrical equipment leakage simulation device according to claim 5, characterized in that: A measuring port is arranged at the gas outlet of the trace mass flow controller, and a tracer gas leak detector is arranged at the measuring port.

9. A method for detecting leakage of clean air insulated electrical equipment, implemented by using the clean air insulated electrical equipment leakage simulation device according to any one of claims 1 to 8, characterized in that: include: Step 1, vacuum the GIL busbar; Step 2: After filling the vacuum GIL busbar with clean air, the value indicated by the digital pressure gauge is used as the total pressure of the mixed gas; Step 3: When charging the GIL busbar filled with clean air with tracer gas, the amount of tracer gas charged is controlled using the indication of the digital pressure gauge to obtain a plurality of gradually increasing tracer gas partial pressures, and a plurality of tracer gas partial pressure changes are obtained by calculation; The concentration of the tracer gas in the mixed gas is calculated based on the ratio of the change in the tracer gas partial pressure to the total pressure of the mixed gas on the GIL busbar. The concentration of the tracer gas is controlled within the preset concentration range. Step 4: Under different tracer gas partial pressures, the leakage rate at each simulated leakage point is controlled to be 0.2 ml / min, and each simulated leakage point is continuously detected, and the time when the tracer gas is detected at each simulated leakage point is recorded; Step 5: Based on the test results at different tracer gas partial pressures, determine the relationship between the tracer gas concentration and the diffusion speed and direction of the tracer gas in the GIL busbar, which serves as the data basis for leakage detection of clean air insulated electrical equipment.

10. The clean air insulated electrical equipment leakage detection method according to claim 9, characterized in that: In step 2, the clean air charging device is turned on, and the three-way valve is rotated to the internal conduction state between the common port and the first port, and clean air is charged into the GIL busbar; The rated pressure of the GIL busbar is set according to the manufacturer's requirements; After stopping the charging of clean air, turn the three-way valve to the closed state and let it stand; The rated pressure of the GIL busbar is taken as the total pressure of the mixed gas.

11. The clean air insulated electrical equipment leakage detection method according to claim 9, characterized in that: In step 3, the tracer gas charging device is turned on, and the three-way valve is rotated to the internal conduction state of the common port and the second port, and the tracer gas is charged into the GIL busbar filled with clean air; after stopping the tracer gas charging, the three-way valve is rotated to the closed state; Among them, the indication of the digital pressure gauge is the partial pressure of the tracer gas.

12. The clean air insulated electrical equipment leakage detection method according to claim 9, characterized in that: The preset concentration range of the tracer gas is 0.1% to 0.2%.

13. The clean air insulated electrical equipment leakage detection method according to claim 9, characterized in that: In step 4, each simulated leakage point is continuously detected using a tracer gas leak detector, the time when the tracer gas is detected at each simulated leakage point is recorded, and the change in the tracer gas concentration is detected at the same time.

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